The proliferation of transaction cards, which allowed the cardholder to pay with credit rather than cash, started in the United States in the early 1950s. Initial transaction cards were typically restricted to select restaurants and hotels and were often limited to an exclusive class of individuals. Since the introduction of plastic credit cards, the use of transaction cards have rapidly proliferated from the United States, to Europe, and then to the rest of the world. Transaction cards are not only information carriers, but also typically allow a consumer to pay for goods and services without the need to constantly possess cash, or if a consumer needs cash, transaction cards allow access to funds through an automatic teller machine (ATM). Transaction cards also reduce the exposure to the risk of cash loss through theft and reduce the need for currency exchanges when traveling to various foreign countries. Due to the advantages of transaction cards, hundreds of millions of cards are now produced and issued annually, thereby resulting in need for companies and individuals to protect against forgery and theft.
Initially, the transaction cards often included the issuer's name, the cardholder name, the card number, and the expiration date embossed onto the card. The cards also usually included a signature field on the back of the card for the cardholder to provide a signature to protect against forgery and tempering. Thus, the initial cards merely served as devices to provide data to merchants and the only security associated with the card was the comparison of the cardholder signature on the card to the cardholder signature on the receipt. However, many merchants often forget to verify the signature on the receipt with the signature on the card.
Due to the popularity of transaction cards, transaction cards now also include graphic images, designs, photographs and security features. One security feature now incorporated is a diffraction grating, or holographic image, which appears to be three dimensional and which substantially restricts the ability to fraudulently copy or reproduce transaction cards because of the need for extremely complex systems and apparatus for producing holograms. A hologram is produced by interfering two or more beams of light, namely an object beam and reference beam, onto a photoemulsion to thereby record the interference pattern produced by the interfering beams of light. The object beam is a coherent beam reflected from, or transmitted through, the object to be recorded, such as a company logo, globe, character or animal. The reference beam is usually a coherent, collimated light beam with a spherical wave front. After recording the interference pattern, a similar wavelength reference beam is used to produce a holographic image by reconstructing the image from the interference pattern. However, forgers have developed counterfeiting methods. One response to the increased prevalence of counterfeiting has been to produce holograms of increasing complexity, but this has also led to increased cost. Other approaches have relied upon the use of covert images and special authentication or verification equipment, e.g., a laser, to enable the detection of such images, but such equipment has often been expensive and difficult to use. Thus, there is a continuing need in the art for secure articles that are extremely difficult to counterfeit, that can be cost-effectively produced, and that can be easily and inexpensively authenticated or verified under field conditions.
The transaction card industry started to develop more sophisticated transaction cards that allowed the electronic reading, transmission, and authorization of transaction card data for a variety of industries. For example, magnetic stripe cards, smart cards, and calling cards have been developed to meet the market demand for expanded features, functionality, and security. In addition to the visual data, the incorporation of a magnetic stripe on the back of a transaction card allows digitized data to be stored in machine readable form. As such, magnetic stripe reader are used in conjunction with magnetic stripe cards to communicate purchase data received from a cash register device on-line to a host computer along with the transmission of data stored in the magnetic stripe, such as account information and expiration date. The magnetic strips are susceptible to tampering, have a lack of confidentiality of the information within the magnetic stripe, and have problems associated with the transmission of data to a host computer.
U.S. Pat. No. 6,468,379 (Naito et al.) discloses a thermal donor and receiver where a security layer could be transferred as a donor layer to the thermal substrate. This forgery preventative layer could contain special decorative effect, hologram layer, a diffraction grating, or florescent materials. This layer would most likely be placed over the thermal image making it susceptible to scratches, wear, and tampering. Furthermore, the diffraction grating and hologram are easily be copied by new reproduction methods available.
U.S. Pat. No. 5,881,196 (Phillips) discloses The use of Wavelength filtering in the cladding layers using interference coatings and colorants produces waveguide modes of different colors. While it is a quick and simple way of testing for authenticity, the color shift may be produced by different means making it vulnerable to counterfeiting. It is desirable to have the light exiting the waveguide in more than one area of the device to make counterfeiting more difficult.
U.S. Pat. No. 6,446,865 (Holt et al.) discloses a badge that is illuminated with a visible wavelength of light and is reflected by a retroreflective film. An imaging system detecting the reflected light from the retroreflective film on the badge and detecting the reflected light from the physical characteristic of the person wearing the badge. The two imaging systems are a Sequential Laser Raster Scanning System and a Simultaneous CCTV Image Frame Freeze System. While this invention provides a high level of security, a machine is required to read the information and determine the authenticity of the ID card. The imaging system would be cost prohibitive and would be very difficult to be made into a portable authenticating system. It would be desirable to have an easily viewable way of detecting the authenticity of a security document and to have a device that had both optical and electrical means of authentication.
U.S. Pat. No. 6,291,150 (Camp at al.) and U.S. Pat. No. 4,948,719 (Koike et al.) disclose the use of a metallic layer in silver halide imaging elements. Silver halide is very sensitive to metals in sensitizing the emulsion and in processing the images. The metal can cause fogging or can leach out and contaminate the processing chemistry forming defects on the finished image. Silver would be the most suitable metal because it is also in the silver halide imaging emulsion, but even silver could create contamination and printing issues. Other metals are generally excluded because of the possible reaction and sensitization of the silver halide. It would be preferable to use a printing technology what is not restricted in the use of reflective layers. There is also a possibility of delamination of the metal and the photosensitive layer during, before or after development because of poor adhesion to the metal layer. Furthermore, Camp and Kiole used substantially uniform blanket coatings of metal. It would be more useful to have a patterned metal coating for a security application because it more difficult to counterfeit, copy, or scan. The inventions only utilize the optical properties of the metallic layer. Metallic layers have other unanticipated features and there remains a need in the industry for a feature to have both electrical and optical security elements.